

'''
bike类
'''
class Bike:

    def __init__(self, identity, name, quantity, price):
        self.__identity = identity
        self.__name = name
        self.__quantity = quantity
        self.__price = price

    @property
    def id(self):
        return self.__identity

    @property
    def value(self):
        return self.__quantity * self.__price

    def name(self):
        return self.__name